North Wales Fire and Rescue were called out in the early hours of Monday after a woman set fire to her microwave while cooking two Christmas puddings.
Fire services were called to the property in St Asaph just after midnight with two appliances from Rhyl and Abergele attending.
Crews inspected the microwave before removing it from the property.
A spokesman for North Wales Fire and Rescue said: "We were called at 00.03 on Sunday night to a building fire on Lower Street in St Asaph. The cause was accidental.
"A microwave at the property had caught fire. Two appliances attended from Rhyl and Abergele.
"The cause was two Christmas Puddings catching fire in the microwave.
"Crews inspected the microwave before removing it."